IsaacWislon82

@betsie: That's what I was trying to get at here, who *can* win is Asa, Jordan, Amaury, who *will* win is Vali, but I suppose that level of pedantic is too much for even PB commenters haha

2019 overall pt 2? Would be awesome

@suspended-flesh: ...roughly half the article is showing the points breakdowns of the 3/4 categories that already have a mathematically determined winner

I feel like Vali would've made a more appropriate thumbnail photo than Asa here

@rrolly: That should be a factor of the casing not the tread, and the "new DH" casing is being applied to all Maxxis DH tires. Also, new DH casing is stiffer than old Maxxis DH, especially the sidewalls, its only "softer" because you can get away with lower psi

@just6979: The authors specifically cite chain line extension as the only mechanism for [3] and as one of the major mechanisms for [4] (they don't make any attempt to determine if chain oscillation or chain line extension is more driving): Section 3.3 Cassette Forwards: "The third category describes the starting torque required to initiate the rotation of the cassette caused by the chain line extension" Section 3.4 Cassette Backwards: "The last category represents a torque generated by stopping the reverse rotation of the cassette. The cassette was previously set in positive rotation due to suspension movement and therefore a sagging chain." The operative word here in Seb's recap is "could", but that is ultimately just speculation on his part

That's what I was thinking too... wasn't the DHX billed basically as "the tire Jackson kept winning on last year"?

Worth pointing out though: [1], [2] (sometimes), [3], and [4] are related to frame kinematics and all four are all mitigated by Ochain

Very interesting to see that inertia of the cassette itself was observed more than forces from cassette engagement... definitely a win for the crank-based systems over the hub-based ones. However I do need to point out a major detail it seems Seb is missing here- 3.5/4 described conditions are theoretically increased by a "high pedal kickback" frame kinematic: -pedal kickback of course, defined as cassette engagement -locked wheel is a mix -->increases traditional PK because hub angular velocity is zero -->can't rotate the cranks to balance (kinematic is irrelevant) -cassette forwards is directly driven by chain line growth and diameter difference between chainring/cog -cassette backwards is indirectly driven by chain line growth and diameter difference between chainring/cog, which defines the amount of slack the derailleur spring takes up So it seems to me that PK is still very much a relevant kinematic for suspension design... even if the exact mechanism of why is a little messier than it first seems.

No. The study says crank torque measured due to engagement of the cassette is rare, but crank torque due to acceleration of the cassette (forwards or backwards) is real, frequent, and measurable. Both of these are caused by chain line extension